Antinociceptive and Anti-edematous Activities of the Essential Oils of Two Balkan Endemic Laserpitium Species

In this paper antinociceptive and anti-edematous effects are examined of the essential oils of the underground parts of two Balkan endemic Laserpitium species (Apiaceae), L. zernyi and L. ochridanum. Furthermore, the essential oil of the underground parts of L. ochridanum is chemically characterised by GC and GC-MS. Antinociceptive and anti-edematous effects were measured in a rat model of localized inflammation, induced by carrageenan, using apparatus for the modified paw-pressure test, and plethysmometer, respectively. The effects of both Laserpitium essential oils were measured after oral gavage administration to male Wistar rats in doses of 25, 50 and 100 mg/kg. The main constituents of L. ochridanum essential oil were: alpha-pinene (33.2%), alpha-bisabolol (10.3%) and chamazulene (14.9%). The essential oil of L. zernyi was previously shown to be rich in alpha-pinene (31.6%) and alpha-bisabolol (30.9%). Both examined essential oils produced a significant dose-dependent antinociceptive effect. The corresponding ED50 +/- SEM in producing antinociception were 45.9 +/- 4.9 mg/kg and 42.4 +/- 2.1 mg/kg for L. zernyi and L. ochridanum oil, respectively. Both essential oils also significantly reduced paw edema in a dose-dependent manner. The estimated ED50 +/- SEM values for the anti-edematous effect were 36.3 +/- 4.5 mg/kg for L. zernyi oil and 45.1 +/- 11.3 mg/kg for L. ochridanum oil. These results suggest that the essential oils of both investigated Laserpitium species may be effective against pain and edema present in various inflammatory conditions.